- Renal: Calculated creatinine clearance > 80 ml/min using the MDRD formula according to Levey 2005: Glomerular filtration rate (GFR) (ml/min/1.73 m²) = 186 x (serum creatinine /0,95)^-1.154 x (age)^-0.203 x (0.742 females) x (1.21 in black patients)